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121.
Optimal control problem governed byy=Ay + Bu, y(0)=y (T), =±1 are studied, whereA is the infinitesimal generator of a nonasymptotically stableC
o semigroup andB is a linear operator from a controller spaceU into a state spaceH. Both distributed (B L(U, H)) and boundary cases (B L(U, (D(A
*)))) are investigated. Some applications to periodic control of wave equations are given.This work was supported by the National Science Foundation under Grant No. DMS-91-11794. 相似文献
122.
123.
Viorel ArnĂutu 《Numerische Mathematik》1982,38(3):393-416
Summary A method for approximating the optimal control and the optimal state for a class of distributed control problems governed by variational inequalities is given. It uses a Rayleigh-Ritz-Galerkin scheme, regularising techniques and a gradient algorithm. A numerical example is given. 相似文献
124.
Phosphorylation of RAF Kinase Dimers Drives Conformational Changes that Facilitate Transactivation
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Dr. Pablo G. Jambrina Dr. Nora Rauch Dr. Ruth Pilkington Dr. Katja Rybakova Dr. Lan K. Nguyen Prof. Boris N. Kholodenko Dr. Nicolae‐Viorel Buchete Prof. Walter Kolch Dr. Edina Rosta 《Angewandte Chemie (International ed. in English)》2016,55(3):983-986
RAF kinases are key players in the MAPK signaling pathway and are important targets for personalized cancer therapy. RAF dimerization is part of the physiological activation mechanism, together with phosphorylation, and is known to convey resistance to RAF inhibitors. Herein, molecular dynamics simulations are used to show that phosphorylation of a key N‐terminal acidic (NtA) motif facilitates RAF dimerization by introducing several interprotomer salt bridges between the αC‐helix and charged residues upstream of the NtA motif. Additionally, we show that the R‐spine of RAF interacts with a conserved Trp residue in the vicinity of the NtA motif, connecting the active sites of two protomers and thereby modulating the cooperative interactions in the RAF dimer. Our findings provide a first structure‐based mechanism for the auto‐transactivation of RAF and could be generally applicable to other kinases, opening new pathways for overcoming dimerization‐related drug resistance. 相似文献
125.
Alia C. Tenchiu Monica Ili Florea Dumitracu Adrian C. Whitwood Viorel Cîrcu 《Polyhedron》2008,27(18):3537-3544
The synthesis and characterization (elemental analysis, 1H and 13C NMR spectroscopy and single crystal X-ray diffraction) of the first ortho-metallated Pd(II) complexes containing N-benzoyl thiourea ligands are described. Four of these compounds showed liquid crystal properties which were investigated by mean of DSC and polarised light microscopy and their mesogenic properties are compared to those of ortho-metallated imine Pd(II) complexes with other types of co-ligands. 相似文献
126.
Research on Chemical Intermediates - A series of mono- and di-cationic pyridinium salts with one or two promesogenic cyanobiphenyl groups and different counterions, bromide, dodecylsulfate or... 相似文献
127.
Viorel Vâjâitu 《Journal of Geometric Analysis》1998,8(1):163-177
We consider bounded and q-complete domains in
C
n
with
C
2
boundary. We show that they enjoy special q-convexity properties, i.e., they admit q-convex bounded exhaustion function and
their closure do have a fundamental system of (q + 1)-complete neighborhoods. Moreover, we produce an example of a q- complete domain (which we called the q-worm) with smooth boundary
whose closure does not possess a fundamental system of q-complete neighborhoods.
Finally, extensions of these results to p-complete manifolds are given. 相似文献
128.
F.?Dumitra?cu M.?R.?CairaEmail author C.?Draghici M.?T.?Caproiu L.?Barbu A.?Badoiu 《Journal of chemical crystallography》2005,35(5):361-365
The objective of the study was to confirm by X-ray analysis the phenomenon of helical chirality inferred from solution 1H-NMR data for a series of derivatives based on the novel pyrrolo[1,2-a][1,10]phenanthroline system. The syntheses of the title compounds and their 1H-NMR data are presented. Crystals of the representative compound ethyl, 1-(4-phenylbenzoyl)-pyrrolo[1,2-a][1,10]phenanthroline-3-carboxylate, with molecular formula C31H22N2O3, were found to crystallize in the triclinic system, space group P 1 with a = 7.8541(1), b = 11.2605(2), c = 13.4093(3) Å, = 92.244(1), = 90.292(1), = 106.475(1) and Z = 2. The X-ray analysis revealed the predicted helicity of the phenanthroline system as well as its origin, namely the proximity of the pyridine N atom and the carbonyl C atom of the phenylbenzoyl residue, with non-bonded distance N s C of only 2.465(2) Å. A secondary, but significant distortion, involving displacement of the carbonyl C atom by more than 0.5 Å from the pyrrole ring, was evident. The crystal structure is maintained by C–H s O hydrogen bonds and – interactions. 相似文献
129.
Herein, we present some aspects regarding the iodination/bromination of 4-hydroxycoumarin or its O-methyl or O-acetyl derivatives with iodine monochloride or iodine monobromide as halogenation reagents. Also, the investigation of photochemical transformation of the three 3-iodocoumarins was investigated for the first time. 相似文献
130.
Marcela Stoia Oana ?tef?nescu Gabriela Vlase Lucian Barbu-Tudoran Mirela Barbu Mircea ?tef?nescu 《Journal of Sol-Gel Science and Technology》2012,62(1):31-40
This paper presents a study regarding the formation of hybrid gels starting from tetraethyl orthosilicate (TEOS), polyvinyl
alcohol (PVA) and 1,3-propanediol (PD) and their thermal evolution to mesoporous silica matrices. The possibility of obtaining
homogenously dispersed cobalt ferrite inside the silica matrix starting from (TEOS–PVA–PD–Metal Nitrates) gels was also studied.
The formation of the hybrid gels TEOS/PVA/PD with different compositions was studied by FT-IR spectrometry and thermal analysis,
in order to evidence the interaction between the diol with the organic and the inorganic polymers. Both thermal analysis and
FT-IR spectrometry have evidenced the formation of physical and chemical interaction between polyols and the siloxane network.
Elemental mapping performed by SEM-EDX technique evidenced the formation of homogenous hybrids both in the presence of the
absence of 1,3-propanediol. SEM images of the powders obtained by annealing the hybrid xerogels at 600 °C have evidenced the
formation of mesoporous silica. By thermal treatment of the (TEOS–PVA–PD–Metal Nitrates) gels, 30%CoFe2O4/70%SiO2 (mass percent) nanocomposites uniformly dispersed in silica matrix with characteristic magnetic properties, have been successfully
synthesized. 相似文献